java - 有没有办法让 g.drawstring 显示随机字符串

Question

首先，我做了一些搜索，但似乎找不到任何东西。有没有一种方法可以使用 g.drawstring 显示随机字符串？这是我现在拥有的:

g.drawString("$" + buttonPrice[i], button[i].x + itemIn, button[i].
y + itemIn - 5);
g.setFont(new Font("Courier new", Font.BOLD, 14));
g.drawString("here is a string",10 , 520);

Answer 1

"what I am trying to do is have an array or similar of strings to chose from and have it display a random string from the array"

我不确定您希望如何随机选择单词，但在下面的代码中，我所做的是使用一个 Timer ，其注册的监听器回调获取 a 的随机索引字符串的列表。已经有一个 word 变量，所以我只需创建 word = list.get(randomIndex); 然后调用 repaint()。您可以通过按按钮或其他操作轻松执行类似的操作。

    private List<String> list = new ArrayList<>();
    private Random random = new Random(System.currentTimeMillis());
    private String word;

    public StringPanel() {
        for (int i = 1; i <= 100; i++) {
            list.add("Word " + i);
        }

        word = list.get(0);

        Timer timer = new Timer(500, new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                int rand = random.nextInt(list.size());
                word = list.get(rand);
                repaint();
            }
        });
        timer.start();
    }

    ....
    @Override
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
        ...
        g.drawString(word, x, y);
    }

<小时/>

这是完整的代码

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.Timer;

public class TestRandomString {

    public TestRandomString() {

        JFrame frame = new JFrame("Test Card");
        frame.setContentPane(new StringPanel());
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setVisible(true);
    }

    public class StringPanel extends JPanel {

        private static final int D_H = 500;
        private static final int D_W = 500;
        private int x = 50;
        private int y = 50;

        private List<String> list = new ArrayList<>();
        private Random random = new Random(System.currentTimeMillis());

        private String word;

        Font font = new Font("impact", Font.PLAIN, 28);
        int wordWidth;
        int wordHeight;

        public StringPanel() {
            for (int i = 1; i <= 100; i++) {
                list.add("Word " + i);
            }

            word = list.get(0);


            Timer timer = new Timer(500, new ActionListener() {
                @Override
                public void actionPerformed(ActionEvent e) {
                    int rand = random.nextInt(list.size());
                    word = list.get(rand);
                    x = random.nextInt(D_W - wordWidth);
                    y = random.nextInt(D_H) + wordHeight;

                    repaint();
                }
            });
            timer.start();
        }

        @Override
        protected void paintComponent(Graphics g) {
            super.paintComponent(g);
            FontMetrics fm = g.getFontMetrics(font);
            wordWidth = fm.stringWidth(word);
            wordHeight = fm.getAscent();

            g.setFont(new Font("impact", Font.PLAIN, 28));
            g.setColor(Color.BLUE);
            g.drawString(word, x, y);
        }

        @Override
        public Dimension getPreferredSize() {
            return new Dimension(D_H, D_W);

        }
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                new TestRandomString();
            }
        });
    }
}